In a principal aspect the present invention relates to a pliers which is especially useful for clamping hoses and other objects and for maintaining a tightly closed or clamped position on the object such as a hose.
Vehicle repair operations and other mechanical repair situations often require that a hose or some other object be gripped and clamped so as to maintain the hose or the object in a desired compressed condition. This result is also often desired in medical applications wherein a clamping action is desired to close a vessel for example. However, the clamping action must be limited in terms of its pressure and degree of closure so that when a clamped condition is reached, the vessel will not be ruptured or damaged. The same desire is applicable to vehicle repair and other mechanical repair operations involving hoses or other items that must be clamped or joined together from time to time.
Various prior art proposals and solutions have been tendered to accomplish such objectives. Adjustable clamps comprise one such solution. So called xe2x80x9cchannel lockingxe2x80x9d pliers provide another solution. Various types of tools have been proposed including tools of the type of disclosed in U.S. Pat. No. 5,005,450 for a self locking tool and various patents cited therein. Other types of clamping plier devices are depicted in the following U.S. Pat. No. 682,701; U.S. Pat. No. 2,574,909; U.S. Pat. No. 1,717,726; U.S. Pat. No. 1,450,875; U.S. Pat. No. 1,026,270; U.S. Pat. No. 2,370,308; U.S. Pat. No. 3,257,878; U.S. Pat. No. 2,787,925; and U.S. Pat. No. 3,126,775. Each of these solutions has benefits and disadvantages. There has remained, however, a desire to provide a clamping mechanism or tool for hoses and other objects which provides a positive closure of the clamping jaws with limited clamping pressure or travel of the jaws toward one another yet which provides a retentive force that will appropriately close a hose and hold with the desired degree or amount of pressure. These and other objectives inspired the development of the present invention.
Briefly, the present invention comprises a pliers construction which includes four pivotally connected members. Thus included in the pliers construction is a first handle member with a first jaw, a second handle member which is pivotally connected to a separate, second jaw and the first handle member and a linkage bar pivotally connected to the second jaw at one end and engaging its opposite end by means of a cam pin with a pair of opposed cam slots defined in the first and second handle members. The interaction of the cam pin carried by the link and the cam slots associated with the handles provides a locking action when the handles are moved together. With the particular construction of the invention it is possible to provide a clamping action more easily because the handles may be more closely spaced and the extent of travel of the handles reduced in order to move the jaws between the open and clamped positions. Thus, the clamping action by the pliers can be affected more easily by a mechanic or other user of the pliers construction. The jaws may include optional pivotal plates which typically and preferably comprise flat planer plates that apply opposite and equally opposed forces of the opposite sides of a hose or other object when the jaws are closed.
Thus it is an object of the invention to provide an improved clamping pliers.
It is a further object of the invention to provide a clamping pliers comprised of four separate elements including a first lever arm or handle which includes an integrated jaw, a second, separate lever arm or handle, a separate second jaw, and a connecting link. The two handles and jaws are pivotally connected and the link interconnects the second jaw with overlapping cam slots in the handles.
It is yet another object of the invention to provide a pliers construction which enables efficient use of amount of travel associated with the handles of the pliers in order to effect a clamping action.
Yet a further object of the invention is to provide a four component clamping pliers which includes a single pivot for two handles and the jaws of the pliers, and a link which controls the interaction of the movement of the handles and jaws.
Yet another object of the invention is to provide a clamping pliers which is easily manufactured, easily utilized by mechanics, rugged and economical.
These and other objects, advantages, and features of the invention will be set forth in the detailed description which follows.